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"Pretty much" is a phrase which is often translated as "casi", and "more or less" is a phrase which is often translated as "más o menos". Learn more about the difference between "pretty much" and "more or less" below.
pretty much( 
prih
-
di
muhch
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. casi 
Have you spent all your money already? - Pretty much.¿Ya te gastaste todo el dinero? - Casi.
b. más o menos 
So Brad hasn't bothered calling you yet? - No, but that's pretty much what I expected.¿Así que Brad no se molestó en llamarte todavía? - No, pero es más o menos lo que me esperaba.
c. prácticamente 
The show's pretty much sold out already.Las entradas para el espectáculo ya están prácticamente agotadas.
more or less(  
mor
or
lehs
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (roughly)